Anybody in Nashville do 80% lower AR "build Parties"?

[peejman]

What they said about milling. Having a good, rigid fixture is very important. If the part is moving or rattling, it'll chatter like crazy. Surface finish and dimensional control will be terrible.

Make small cuts.... 0.025" at the most. Make a pass, the make another pass (called a spring pass) without moving anything. If it makes chips the 2nd time, your cutting too much or the part is moving.

[tnguy]

Bump. Will be interested in this soon.

 

Will have lower & jig. If someone is willing to host the party, that would be good otherwise plan is to wait for the HF mill to go on sale (I've seen it as low as 400) and get that. If I get that, I'll probably mod it to CNC at some point. Then we might be looking at some 0% lowers :)

 

No rush on this, just testing the waters.

 

Oh, if you're thinking of getting into this, tacticalmachining.com is having a christmas sale right now.

Edited December 20, 2013 by tnguy

[broylz]

I really need to get back on this but its a bit cold lately in an uninsulated garage. might be worth messing with since we have a warm weekend.

[penguincomp]

Wish I had a clue about machining.

[tnguy]

From what I understand, the jig takes a lot of the effort out of it. Most of what's needed is a slow, steady hand.

[Guest kcraig514]

Running a mill bit is a completely different animal than a regular drill bit. I will go ahead and apologize if you already are familiar with what I'm about to say.
You want to take off very small amounts of material each pass. If the bit is making anything but a very light smooth cutting sound it will show up in the finished product. If your getting any kind of chatter your speed is to high, you trying to remove to much material to fast or your putting to much pressure on it.
Also, if your running a mill/drill the less extended the arbor is the smoother and more precise you will be. The mill/drills tend to have a bit of flex, especially when extended way out.
I've got a couple of really nice machining textbooks that are easy to read and take you from A to Z and if your a bit of a machining novice like me, I would be happy to loan them to you. I'll just have to unpack them.

I've been a machinist 25 yrs and another good tip when machining aluminum is good ol' WD40. Use it as a cutting fluid and it will help bunches. Just my 2 cents!

[tnguy]

Well, seven years later, I still have a box of 80% lowers :)

[Tobashadow]

On 7/12/2020 at 3:58 PM, tnguy said:

Well, seven years later, I still have a box of 80% lowers

Want to sell one? I have always wanted to mess with one.

[tnguy]

I'll have a think about it. Probably not for much less than I bought it. Note that these are gen 1 (I think) and don't have the rear pin pocket already milled.